It seems to me that what you are proposing is simply a needlessly convoluted way to shift taxation from labour to rental value, by requiring the sovereign - or some proxy for same - to take all land into custody and rent it out, thus substituting its new rental income for the current tax income.

The incidence of taxation is an expression of political power. If you have the political power to move to a monetary system that requires the state to collect and/or tax away a greater proportion of the rental value land than it does today, then you also have the political power to just tax landowners (unless you wish to assume that landowners are stupid - for which there may be a case to be made).

And if you do have the power to tax landowners, then taxing them will be superior to your proposal, because your scheme will not break down gracefully if power swings back to the landholders: A reprivatisation of the land will allow landholders to hold the monetary system hostage until you go off the land standard. That encourages a positive feedback loop going in the wrong direction, to borrow one of ATinNM's stock phrases.

You're basically proposing a fiat system in a cheap tuxedo and with an open back door for takeover by landholders as well as banksters.